1. Field of the Invention
The present invention relates to an image forming apparatus, such as a copier or a printer, which is capable of reading information attached to a toner container.
2. Description of the Related Art
Conventionally, there has been proposed an image forming apparatus configured such that when a toner container having an information recording part (e.g. a barcode) containing serial numbers and information on compatible models and the like is mounted in the image forming apparatus, an optical sensor in the image forming apparatus reads the information recording part (see e.g. Japanese Patent Laid-Open Publication No. 2003-280349).
The image forming apparatus determines, based on the information read by the optical sensor, whether or not the toner container is compatible with the image forming apparatus, and stops the operation of the image forming apparatus when the mounted toner container is incompatible.
Image forming apparatuses differ in in-apparatus temperature between models thereof, and toner-softening temperature is also different between the models. For this reason, when a toner in a toner container incompatible with an image forming apparatus is used, blocking (toner solidification) or the like occurs, which can impair image quality or damage the image forming apparatus.
Therefore, it is required to accurately read the information recording part on the toner container. Further, it is required to avoid stopping the operation of the image forming apparatus based on an erroneous determination that a toner container is incompatible with the image forming apparatus, despite the fact that the toner container is actually compatible.
However, if the distance between the optical sensor and the information recording part changes due to the rotational deflection of the toner container being rotated, the amount of received light decreases or a spot diameter at a reading position changes, which lowers the reading resolution.
In particular, the toner container is formed to be hollow with a thin wall so as to be filled with toner, and hence is difficult to mold with high accuracy, and further the shape of the toner container is apt to change depending on the use environment. Therefore, the toner container tends to have a large rotational deflection, which can cause erroneous reading or result in a reading error.